Clutch



Jan. 22 1924.

J. FIEUX CLUTCH Filed Sent. 5. 1921 5 Sheets-Sheet 2 q d a S Hlfl G 9 l 4., w L. 2. q f f lwlzll a .ma .l a .a x x F M .w u 1 m a2 a au. W .w a n ,m

J. FIEUX Jan. 22 1924.

CLUTCH Filed Sept. f5 1921 3 Sheets-Sheet 3 www/ Patented Jan. 22, 1924.

JEAN FIEUXQ 0F PARIS, FRANCE.

CLUTCH.

Applicatonled September 3, 1921.

To all whom t may concern.'

Be it known that I, JEAN FIEUX, a citizen of the French Republic, and resident of Paris, in the Republic of France, have invented certain new and useful Im rovements in or Relating toy Clutches, of Which the following is a specification.

The present invention has for its object the provision of an improved friction coupling clutch capable of ensuring the auto-.

matic coupling of a motor shaft and a driven shaft and of limiting the effort transmitted With great precision.

In practice the operation of the clutch is independent of the value of the coefficient of friction; the value of the. maximum couple which can be transmitted depends only on the speed of the motor shaft. It is automatically moved into complete coupling position as soon as the resistance of the driven shaft allows of this action and during slipping as soon Y as the resistance becomes excessive. Finally uncoupling or complete disengagement of the tvvo shafts, that is to say, the driving shaft and the driven shaft, can be effected when the Speed of the motor shaft falls below a certain limit.

This invention is characterized by the combined action of centrifugal force and the driving effort of the motor so as to ensure the driving of a clutch of the helical coil type, the effect of the motor couple on this drive being always opposed to the effect of centrifugal action so that. the resultant force Which is applied to the free end of the helical coil in order to create the friction necessary for coupling retains a suitable value during the entire period of slipping.

Biagrammatical and constructional forms of the invention are shown by Way of example in the accompanying drawings.

Figure l is a diagrammatic perspective view of the invention certain parts being shown in section along axial planes.

Figure 2 is an axial section of a constructional form in accordance with the present invention which construction approaches as near as possible the diagrammatic form shown in Figure 1.

Figure 3 is a cross section onv the line wb, Figure 2, the coil being shown in elevation.

-. articulated on a Serial No. 498,452.

an axial section on the line of a constructional form of adapted to the fly Wheel of Figure 4 is e o f, Figure 5 the invention as a motor.

Figure 5 is a cross section on the line c d, Figure 4, thecoil being shown in elevation.

n the diagrammatic arrangement shown in Figure l the motor shaft l is integral With or rigidly connected to a disc 2 or radial arms on which rods are articulated at suitable 'rlistances apart and diametrically opposite each other, the pivotal supports of the said rods being arranged parallel to the axis of the motor shaft and "being provided with heavy or massive heads 4 and 4. A second disc 5 integral with or rigidly connected to a hub 6 is arranged to oscillate freely on an extension of the motor shaft. Rods 7 and 7 terminating in heavy or massive heads 8 and 8 are articulated on the disc 5, the axes of the pivotal supports of the said rodskbe ing disposed parallel to the motor shaft axis. The heads of the rods 3 and 7 are pivotal support common to both the heads of both rods and the heads of the rods 3 and 7 are likewise articulated on a pivotal support common to both rods 3 and 7.

rlfhe deformable arrangement of the groups of masses and the rods which carry them is such that said devices can turn in the direction of the arrow; the motor shaft l turns in advance of the disc 5,- When the -tWo groups of masses 4, 8 and 4', 8 spread apart centrifugally, that is one group relatively to the other and inversel The driven shaft 9 dispose l tension of the motor shaft is integral with or rigidly a disc 1l loosely mounted on the motor shaft. Inside the drum is arranged a frictional 'member formed by a helical spring l2 the two ends of which are subjected to the reactions of the pins 2 and 5 respectively integral With or rigidly connected to the discs 2 and 5, the helical angle of the coil being such that a certain displacement of the motor shaft 1 and of the disc 5 corresponding to a displacement outwardly of the twogroups of masses 4, 8 and 4, 8 may have the effect of increasingy the diameter of the coil so that the outer surface of the on an ex-v connected to a drum 10 closed byl liti - coupling an increase 1n coil becomes applied to the interior surface of the drum.

vThe action o' the construction and arrangement as above described is as follows.

When coupling is incomplete the motorI shaft entrains with it all the members or parts in the interior of the drum in the direction of the arrow and a rotational speed reater than that of the` driven shaft. entrifugal force which acts on the masses l, d and 8, 8 produces reacting .forces which result through the intermediary of the ins 2 and' 5' for pressing the ends oit the elical coil toward each other and thereby diametrically expanding the coil, thus causing a certain friction which constitutes the driving couple actuating the driven shaft. lt should be observed in this case that one end of the helical coil is in contact with the pin 2 integral with or rigidly connected to the motor shaft and that the other end of the helical coil is in contact with the pin 5 integral with or rigidly secured to the oscillating disc 5.

The dri-ving effort of the motor has, on the contrary, the effect of tending to torce the masses towards the centre and consequently of opposing the action ofcentrifugal `torce. rlhis dual action leads to increased efhciency ot' the friction under conditions fully determined by theY motor. During the period of slipping the reaction of the pin 2 on one end of the helical coil increased by the entraining force due to the friction acts to balance the"reaction of the pin 5 on the other end of the helical coil, this latter reaction being due solely to centrifugal force.

lf the helical coil is given a sufficient number of convolutions the reaction of the pin 2 may become very slight relatively to the reaction of the pin 5 no matter what the coefiicient of the frictional surfaces may be. The variations can therefore have a very great eii'ect on the value of the maximum couple transmitted by the `friction because the e'ect of centrifugal. VJforce is itself constant and quite definite for a given speed of the motor shaft. From this is derived the great precision above referred to in the' limitation of this couple.

When the resisting couple becomes insuficient to ensure a state of equilibruim coi-- respondin to the slipping condition, the clutch action becomes complete. The centrifugal eiect does not diminish as the motor couple, the reaction of the pin 2 increases and immediately eects by excess frictional action the complete coupling of the helical coil and the drum.

The apparatus being now in com lete action an increasing value o the resisting couple has for its eiect to cause the value of the motor couple 'and consequently to reduce the reaction of incisos the pin 2' on the free end of the helical coil. When this reaction has been suiiiciently reduced slipping again taires place.

lt should be observed that in this airangement the reaction of the pins 2 and are effected directly on the ends of a frictional member which has not..` as in the usual cone clutch, any natural tendency to engagement'nor, as in clutches of the disc type, the inconvenience of being difficult in its control under load by the friction of the discs on vtheir-driving keys or slots, The automatic control of this riction system adopted for the realization of the resent invention is eected therefore un er the best possible conditions.

On the other hand this nrictional system has the advantage of eecting the rictio'i on cylindrical surfaces which are applied in such manner as to effect complete and perfeet Contact between the rictional surfaces by reason of the iexibilty of the helical coil, the said surfaces being capable of being lubricated in a regular and abundant manner. The apparatus can always be constructed of such dimensions that the coefhcient of wear and tear on the helical coil under the greatest load does notexceed the coeiicient required for an ordinary transmissionbearing. The wear and tear is therefore very slight; by reason of the deformability of the system carrying the centrifugal masses, the apparatus automatically recovers itself.

ln the constructional form shown in Figures 2 and 3, the essentiall parts forming the diagrammatical apparatus hereinbefore vdescribed are provided with the same reference numerals. On each of the discs 2 and 5 are articulated a suitable number of rods having massive twin heads as hereinbefore explained. In general the number of heads may be suiicient so that the space comprised between the two discs can be fully utilized. The disc 2 and the hub of the disc 5 are provided with projections 22 and 23 which limit the relative angular displacement in such manner that the disc 2 entrains the disc 5 directly when the motor shaft is at first or initially set in rotation. At this moment the centrifugal force has only a very small value.'

In this arrangement the helical coil may be mounted between the pins 2 and 5 with a certain initial tension opposed to the action of centrifugal force so as to have only a useful driving effect which comes into operation at acertain speed of the motor shaft.

In; the constructional form shown in Figures 4 and 5 the motor shaft 1x3 is integral `with 'or rigidly connected to the disc 2a forming the mam part of the ily wheel of the motor and carrying the axes of articulation of .siii rods 3a each terminating in a massive head 4 of a form which will fully utilize' the intervening space. A second disc integral with or rigidly connected to a hub 6*v is adapted to oscillate freely on a trunnion 14 on the disc 2 and on the driven shaft 9 which is centered by means of a ball bearing in the bore of the disc 2", the opposite end of the said driven shaft bein supported by a cover piece 15 integral wit or rigidly connected to the said disc.

The hub of the disc 5'* carries the axes of articulation of six rods 16 and six rods 17 each of which are terminated by massive heads 18"L and 19.

The rods 3*,16 and 17* are articulated together in a manner so as to form a deformable lsystem adapted to turn in the direction indicated by the arrow, the motor shaft rotating in advance of the disc 5* when the centrifugal group 4, 18 and 19* spreads apart from the axis of rotation and inversely.

The driven shaft 9^ is rigid with an open drum 10a containing a helical coil 12' each end of which carnes a pin. IThe pin 20 on the fixed end engages in a slot of suitable ;form provided on the disc 2*. The pin 21 at the fixed end engages in a slot formed in the disc 5a. The direction of the angle of the helical coil is such that a certain displacement of the two discs corresponding to a displacement towards the exterior of the centrifu al groups of masses has for its effectto increase the diameter of the helical coil and to cause the exterior surfaces of the helical coil to apply themselves to the interior surfaces of the drum.

As in the preceding arrangement, the relative angular displacements of the discs 2 and 5'* are limited by stops at the moment of starting. These stops are formed by bosses 24* and 25 which carry the axes of articulation of rods 3 and 16.

In the interior of the hub and projecting from the disc 5 is a spring 26l which operates on tension and the ends of which exertv their action, one on the disc 2 by means of the pin 27, the other end exerting its action on the disc 5l by means of a pin 28 and an adjusting washer 29'* which-is fitted and in practice ma be also threaded in an annular recess in t e hub. The tension of this spring always acts in opposition to the action of centrifugal force and can be regulated by suitable adjustment of the Washer 29at on the disc 5. It has for its object to oppose the formation of a driving couple for ll speeds of the motor below a given spee The cover 15 is provided with ribs 30 so as to dissipate rapidly the heat generated when the device is in use.

Having now particularly described and y ascertained the nature of my said'invention and in what manner the same is to be perforn ed, I declare that what I claim is:

In a clutch, the combination of a driving shaft, a driven shaft, a drum fast to the driven shaft, a coiled friction spring arranged in the drum, a sto on the driving shaft engaging one end o said spring, an element loose on the driving shaft and having a stop engaging the other end of the spring, a centrifugally movable weight and arms pivotally connecting said weight to the driving shaft and to the last named stop.

In witness whereof I alixed my si ature` JEAN FI UX. 

